Download York SUNLINE 2000 B1CH180 Operating instructions

®
SUNLINE 2000
GAS / ELECTRIC
SINGLE PACKAGE AIR CONDITIONERS
INSTALLATION INSTRUCTION
530.18-N6Y (500)
Supersedes: 530.18-N6Y (1298)
035-12552
MODELS D2CG180 & 240 (STY. B)
(8.4 - 8.5 EER)
208/230/575
VOLT ONLY
208/230/460
VOLT ONLY
SAFETY CONSIDERATIONS
Due to system pressure, moving parts and electrical
components, installation and servicing of air conditioning
equipment can be hazardous. Only qualified, trained, service
personnel should install, repair, maintain or service this
equipment.
Observe all precautions in the literature, on labels and tags
accompanying the equipment whenever working on air
conditioning equipment. Be sure to follow all other safety
precautions that apply.
Wear safety glasses and work gloves, and follow all safety
codes. Use a quenching cloth and have a fire extinguisher
available for all brazing operations.
GENERAL
YORK Model DCG units are single package gas-fired central
heating furnaces with cooling unit designed for outdoor
installation on a rooftop or a slab.
The units are completely assembled on rigid, permanently
attached base rails. All piping, refrigerant charge, and electrical
wiring is factory installed and tested. The units require electric
power, gas connection, duct connections, installation of
combustion air inlet hood, flue gas outlet hoods and fixed
outdoor air intake damper (units without economizer or
motorized damper option only) at the point of installation.
FOR YOUR SAFETY
If you smell gas:
1. Open windows.
2. Don’t touch electrical switches; do not use
any phones in the area of the gas leak.
3. Extinguish any open flame.
4. Immediately call your gas supplier from another
location. Follow your gas supplier’s
instructions.
5. If you cannot reach your gas supplier, call the
fire department.
FOR YOUR SAFETY
Do not store or use gasoline or other flammable vapors and
liquids in the vicinity of this or any other appliance.
The gas-fired heaters have aluminized-steel tubular heat
exchangers and spark ignition with proven pilot.
INSPECTION
As soon as a unit is received, it should be inspected for possible
damage during transit. If damage is evident, the extent of the
damage should be noted on the carrier’s freight bill. A separate
request for inspection by the carrier’s agent should be made in
writing. Refer to Form 50.15-NM for additional information.
REFERENCE
Additional information on the design, installation, operation and
service of this equipment is available in the following reference
forms:
•
•
•
•
•
44-320-10
530.18-N6.1V
530.18-N6.2V
530.18-N6.3V
530.18-N13Y
- Barometric Relief Damper Accessory
- Propane Conversion Accessory (USA)
- High Altitude Accessory (Nat. Gas)
- High Altitude Accessory (Propane)
- Coil Guard Installation
Renewal Parts:
• Refer to the Renewal Parts Manual for complete listing of
replacement parts on this equipment.
All forms referenced in this instruction may be ordered from:
Standard Register
2101 West Tecumeseh Road
Norman, Oklahoma 73069
Toll Free Fax: (877) 379-7920
Toll Free Phone: (877) 318-9675
APPROVALS
Design certified by ETL & CGA as follows:
1. For use as a forced air furnace with cooling unit.
2. For outdoor installation only.
3. For installation on combustible material.
4. For use with natural gas or propane gas.
CAUTION
THIS PRODUCT MUST BE INSTALLED IN STRICT COMPLIANCE
WITH THE ENCLOSED INSTALLATION INSTRUCTIONS AND ANY
APPL ICABL E L OCAL, STATE, AND NATIONAL CODES
INCLUDING, BUT NOT LIMITED TO, BUILDING, ELECTRICAL,
AND MECHANICAL CODES.
WARNING
INCORRECT INSTALLATION MAY CREATE A CONDITION
WHERE THE OPERATION OF THE PRODUCT COULD CAUSE
PERSONAL INJURY OR PROPERTY DAMAGE
Installer should pay particular attention to the words: NOTE, CAUTION and WARNING. Notes are intended to clarify or make
the installation easier. Cautions are given to prevent equipment damage. Warnings are given to alert installer that personal injury
and/or equipment damage may result if installation procedure is not handled properly.
530.18-N6Y
TABLE OF CONTENTS
General ................................................................................ 1
Inspection............................................................................. 1
Reference............................................................................. 1
Approvals ............................................................................. 1
Nomenclature....................................................................... 2
MAINTENANCE & TROUBLESHOOTING
Normal Maintenance ......................................................... 20
Cleaning Flue Passages and Heating Elements ............... 20
Troubleshooting.................................................................. 21
Replacement Parts ............................................................ 23
INSTALLATION
TABLES
Limitations ............................................................................ 3
Location ............................................................................... 3
Rigging and Handling .......................................................... 3
Clearances........................................................................... 3
Ductwork .............................................................................. 3
Fixed Outdoor Air Intake Damper ........................................ 4
Condensate Drain ................................................................ 4
Compressors........................................................................ 4
Filters ................................................................................... 4
Service Access .................................................................... 4
Thermostat........................................................................... 5
Power and Control Wiring .................................................... 5
Combustion Discharge ........................................................ 5
Gas Piping ........................................................................... 5
Gas Connection ................................................................... 6
L.P. Units, Tanks and Piping ................................................. 6
Vent and Combustion Air Hoods.......................................... 6
Optional Economizer/Mot. Damper Rain Hood ................... 7
Optional Power Exhaust Rain Hood .................................... 9
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Description
Page
Unit Application Data ..................................
3
Control Wire Sizes ......................................
5
Gas Heat Application Data .........................
6
Pipe Sizing ..................................................
6
Physical Data ..............................................
9
Electrical Data............................................. 10
Four And Six Point Loads ........................... 12
Supply Air Blower Perf. 15 Ton.................... 13
Supply Air Blower Perf. 20 Ton.................... 14
Static Resistances ...................................... 15
Power Exhaust Performance ...................... 15
Blower Motor and Drive Data...................... 15
Limit Control Setting ................................... 17
Gas Rate - Cubic Feet Per Hour................. 20
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
Description
Page
Typical Rigging............................................
3
Center of Gravity.........................................
3
Fixed Outdoor Air Damper Assembly .........
4
Recommended Drain Piping.......................
4
Typical Field Wiring .....................................
5
External Supply Connection .......................
6
Bottom Supply Connection .........................
6
Vent and Combustion Air Hoods.................
7
Adjusting Enthalpy Setpoint........................
8
Dimensions and Clearances....................... 11
Four and Six Point Loads............................ 12
Gas Valve Piping......................................... 17
Gas Valve and Controls .............................. 17
Typical Gas Valve ........................................ 18
Proper Flame Adjustment........................... 18
Typical Flame Appearance ......................... 19
Belt Adjustment........................................... 19
Pressure Drop versus Supply Air CFM ...... 19
Typical Flue Baffle Installation .................... 21
FIGURES
OPERATION
Cooling System.................................................................. 15
Preliminary Operation Cooling........................................... 15
Cooling Sequence of Operation......................................... 15
Safety Controls (Cooling)................................................... 15
Heating System.................................................................. 15
Safety Controls (Heating)................................................... 16
Heat Anticipator Setpoints ................................................. 16
Pre-Start Check List........................................................... 16
START-UP
Operating Instructions........................................................ 17
Post-Start Check List ......................................................... 17
Manifold Gas Pressure Adjustment ................................... 17
Pilot Checkout .................................................................... 17
Burner Instructions............................................................. 17
Burner Air Shutter Adjustment........................................... 18
Checking Supply Air CFM.................................................. 18
Adjustment of Temperature Rise........................................ 19
Checking Gas Input ........................................................... 19
Secure Owner’s Approval .................................................. 19
PRODUCT NOMENCLATURE
D
2
C
G
1
8
0
N
2
4
0
2
5
PRODUCT CATEGORY
D = Single Package Air Conditioner
(Air Cooled)
PRODUCT GENERATION
2 = 2nd Generation
NOMINAL HEATING
OUTPUT CAPACITY
PRODUCT IDENTIFIER
CG = Gas/Electric
NOMINAL COOLING
CAPACITY
180 = 15 Tons
240 = 20 Tons
GAS
240 = 240 MBH
320 = 320 MBH
FACTORY INSTALLED
HEAT
E
C
FACTORY INSTALLED
OPTION CODE
EC = Sing. Input Economizer
DK = Diff. Input Economizer
FD = Sing. Input Economizer
w/Power Exhaust
CF = Diff. Input Economizer
w/Power Exhaust
BG = Motor Outdoor Air
Damper
VOLTAGE CODE
25 = 208/230-3-60
46 = 460-3-60
58 = 575-3-60
N = Natural Gas
2
Unitary Products Group
530.18-N6Y
INSTALLATION
LIMITATIONS
These units must be installed in accordance with the following
national and local safety codes:
In U.S.A.:
1. National Electrical Code ANSI/NFPA No. 70.
2. National Fuel Gas Code Z223.1.
3. Gas-Fired Central Furnace Standard ANSI Z21.47a.
4. Local gas utility requirements.
In Canada:
1. Current Canadian Electrical Code C22.1.
2. Current Gas Installation Codes CAN/CGA-B149.1 and .2
3. Local plumbing and waste water codes.
4. Other applicable local codes.
Refer to the Unit Application Data table and to the Gas Heat
Application Data table.
After installation, the unit must be adjusted to obtain a
temperature rise within the range specified on the unit rating
plate.
If components are to be added to a unit to meet local codes,
they are to be installed at the dealer’s and/or the customer’s
expense.
Size of unit for proposed installation should be based on heat
loss/heat gain calculation made according to the methods of
the Air Conditioning Contractors of America (ACCA).
This furnace is not to be used for temporary heating of buildings
or structures under construction.
15 TON
20 TON
187 / 253
414 / 506
518 / 630
4500 / 7200 6000 / 9400
57 / 72
25 / 120
1Utilization range “A” in accordance with ARI Standard 110.
2
A low ambient accessory is available for operation down to 0°F.
LOCATION
Use the following guidelines to select a suitable location for
these units.
1. Unit is designed for outdoor installation only.
2. Condenser coils must have an unlimited supply of air.
Where a choice of location is possible, position the unit on
either north or east side of building.
WARNING: E x ce ss ive exp os ur e of this fur nace to
contaminated combustion air may result in
equipment damage or personal injury. Typical
contaminates include: permanent wave solutions,
chlorinated waxes and cleaners, chlorine based
swimming pool chemicals, water softening
chemicals, carbon tetrachloride, Halogen type
r e fr i ge ra nt s, cleaning solvents ( e.g.
perchloroethylene), printing inks, paint removers,
varnishes, hydrochloric acid, cements and glues,
antistatic fabric softeners for clothes dryers,
masonry acid washing materials.
3. For ground level installation, use a level concrete slab with
a minimum thickness of 4 inches. The length and width
should be at least 6 inches greater than the unit base rails.
Do not tie slab to the building foundation.
4. Roof structures must be able to support the weight of the
unit and its options and/or accessories. Unit must be
Unitary Products Group
RIGGING AND HANDLING
Exercise care when moving the unit. Do not remove any
packaging until the unit is near the place of installation. Rig the
unit by attaching chain or cable slings to the round lifting holes
provided in the base rails. Spreaders, whose length exceeds
the largest dimension across the unit, MUST be used across
the top of the unit. Refer to the figure below.
FIG. 1 - TYPICAL RIGGING
TABLE 1 - UNIT APPLICATION DATA
Model Size
208/230-3-60
Voltage Variation,
460-3-60
Min. / Max.1
575-3-60
Supply Air CFM, Min. / Max.
Wet Bulb Temperature (°F) of Air on
Evaporator Coil, Min. / Max.
Dry Bulb Temperature (°F) of Air on
Condenser Coil, Min.2 / Max.
installed on a solid level roof curb or appropriate angle iron
frame.
CAUTION: If a unit is to be installed on a roof curb or special
frame other than a YORK roof curb, gasketing must
be applied to all surfaces that come in contact with
the unit underside.
5. Maintain level tolerance to 1/2 inch maximum across the
entire length or width of the unit.
CAUTION: Before lifitng a unit, make sure that all panels are
in place and that its weight is distrbuted equally on
all cables so it will lift evenly.
Units may also be moved or lifted with a forklift, from the front
or rear only, providing that an accessory skid is used.
LENGTH OF FORKS MUST BE A MINIMUM OF 90".
CAUTION: An adhesive backed label is provided over the
outside of the combustion air inlet opening to
prevent moisture from entering the unit which could
cause damage to electrical components. Allow this
closure label to remain in place until the
combustion air hood is to be installed (refer to Vent
and Combustion Hood Figure).
Refer to the Physical DataTable for unit weights and to the
figure below for approximate center of gravity.
FIG. 2 - CENTER OF GRAVITY
CLEARANCES
All units require certain clearances for proper operation and
service. Installer must make provisions for adequate combustion
and ventilation air in accordance with Section 5.3, Air for
Combustion and Ventilation of the National Fuel Gas Code, ANSI
Z223.1 (in U.S.A.) or Sections 7.2, 7.3 or 7.4 of Gas Installation
Codes CAN/CGA-B149.1 and .2 (in Canada) and/or applicable
provisions of the local building codes. Refer to Dimensions and
Clearances Figure for the clearances required for combustible
construction, servicing, and proper unit operation.
WARNING: Do not permit overhanging structures or shrubs to
obstruct outdoor air discharge outlet, combustion
air inlet or vent outlets.
3
530.18-N6Y
DUCTWORK
Ductwork should be designed and sized according to the
methods in Manual Q of the Air Conditioning Contractors of
America (ACCA).
A closed return duct system shall be used. This shall not
preclude use of economizers or outdoor fresh air intake. The
supply and return air duct connections at the unit should be
made with flexible joints to minimize noise.
The supply and return air duct systems should be designed for
the CFM and static requirements of the job. They should NOT
be sized to match the dimensions of the duct connections on
the unit.
CAUTION: When fastening ductwork to side duct flanges on
unit, insert screws through duct flanges only. DO
NOT insert screws through casing.
Outdoor ductwork must be insulated and
waterproofed.
FIG. 3 - FIXED OUTDOOR AIR DAMPER
Refer to Dimensions and Clearances Figure for information
concerning side and bottom supply and return air duct openings.
from the one-inch NPT female connection on the unit to an open
drain.
It is recommended that, in Canada, the outlet duct be provided with
a removable access panel. It is recommended that this opening be
accessible when the unit is installed in service, and of a size such
that smoke or reflected light may be observed inside the casing to
indicate the presence of leaks in the heat exchanger. The cover
should be attached in a manner adequate to prevent leakage.
An alternate drain connection (one-inch NPT female coupling)
is provided inboard on the same centerline as the exterior
location.
NOTE: The condensate drain operates in a negative pressure
in the cabinet. The condensate drain line MUST be
trapped to provide proper drainage. See figure below.
FIXED OUTDOOR AIR INTAKE DAMPER
This damper is shipped inside the return air compartment. It is
completely assembled and ready for installation. A damper
baffle inside of the hood is adjustable to provide variable
amounts of outdoor air intake on units that are not provided
with an economizer or a motorized damper option. Refer to the
Fixed Outdoor Damper figure.
Gasketing and mounting screws are provided in a parts bag
attached to the hood assembly. Apply gasketing to the three
flange surfaces on the hood prior to installing the hood. Extend
gasketing 1/4 inch beyond the top and bottom of the two side
flanges to insure adequate sealing.
Adjusting the damper to the desired air flow may be done before
mounting the hood into position or (after installation) by
removing the front hood panel or the screen on the bottom of
the hood. Damper baffle in position 1 will allow approximately
10% recirculated air flow, position 2 approximately 15% and, to
allow approximately 25%, remove the damper baffle.
On units with bottom return air applications, install the damper
assembly over the opening in the side return air access panel.
Remove and discard the opening cover and the covering over
the hood mounting holes (used for shipping) before installing.
Secure with the screws provided.
On units with side return air applications, install the damper
assembly on the return air ductwork as close to the unit as
possible. Cut an opening 16 inches high by 18 inches wide in
the ductwork to accommodate the damper. Using the holes in
the hood flanges as a template, drill 9/64 inch dia. (#26 drill)
holes into the ductwork and secure with the screws provided.
CAUTION: If outdoor air intake will not be required on units
with bottom return air applications, the damper
assembly should still be mounted on the side return
air access panel, per the instructions above, to
insure moisture is not drawn into the unit during
operation. The covering over the mounting holes
only need be removed. Do not remove the opening
cover.
CONDENSATE DRAIN
Plumbing must conform to local codes. Use a sealing
compound on male pipe threads. Install a condensate drain line
4
FIG. 4 - RECOMMENDED DRAIN PIPING
COMPRESSORS
Units are shipped with compressor mountings factory-adjusted
and ready for operation.
CAUTION: Do Not loosen compressor mounting bolts.
FILTERS
Two-inch filters are supplied with each unit. Filters must always
be installed ahead of the evaporator coil and must be kept clean
or replaced with same size and type. Dirty filters will reduce the
capacity of the unit and will result in frosted coils or safety
shutdown. Minimum filter area and required sizes are shown in
Physical Data Table.
SERVICE ACCESS
Access to all serviceable components is provided by the
following removable panels:
•
•
•
•
•
•
•
Compressor compartment
Gas Heat compartment (Two panels)
Side Supply & Return Air compartments (Two panels)
Blower compartment (Three panels)
Main control box
Filter compartment
Outdoor Air compartment (Two panels)
Refer to the Dimensions and Clearances Figure for location of
these access panels.
CAUTION: Make sure that all screws and panel latches are
replaced and properly positioned on the unit to
maintain an air-tight seal.
Unitary Products Group
530.18-N6Y
CONTROL WIRING
COOLING / HEATING (24 VOLT THERMOSTAT)
THERMOSTAT1
UNIT TERMINAL
TERMINALS
BLOCK 1TB2
COOLING ONLY (24 VOLT THERMOSTAT)
THERMOSTAT1
TERMINALS
UNIT TERMINAL
RC
BLOCK 1 TB2
RH
R
Y1
Y1
ADD
Y2
Y2
JUMPER
W1
W1
G
B
LED1
LED2
ADD
JUMPER
COM
A1
A2
T
NOT USED
RC
ADD
JUMPER
4
4
Y1
Y2
W1
W2
W2
G
B
X
3
W2
R
Y1
Y2
W1
W2
G
B
X
A1
A2
Y3
RH
3
G
24 VOLT
TRANSFORMER
24 Volt Thermostat 2TH04701024 or 2TH04701524
(with Subbase 2TB04700324).
2Terminal strip 1TB - located on relay board in 24-volt section
of the unit control box.
3Second stage heating is not required on units with a single stage
electric heater.
1
24 VOLT
A1 TRANSFORMER
A2
POWER WIRING
T
L1
LINE VOLTAGE
TERMINAL
L2
BLOCK 2TB
L3
IN CONTROL BOX
TO REMOTE SENSOR
2THO4702224 IF USED
1Electronic programmable thermostat 2ET04700224 (includes subbase).
2Terminal block 1TB- located on relay board in 24-volt section of the unit control box.
3Second stage heating is not required on units with a single stage electric heater.
4Terminals A1 and A2 provide a relay output to close the outdoor economizer dampers
when the thermostat switches to the set-back position.
NOTE: Fans switch must be in "ON" position for minimum ventilation during heater operation.
Refer to the
ELECTRICAL DATA
tables to size the
power wiring, the
fuses and the
disconnect switch.
GROUND LUG
FIG. 5 - TYPICAL FIELD WIRING
THERMOSTAT
The room thermostat should be located on an inside wall
approximately 56 inches above the floor where it will not be
subject to drafts, sun exposure or heat from electrical fixtures
or appliances. Follow manufacturer’s instructions enclosed with
thermostat for general installation procedure. Seven color
coded insulated wires (#18 AWG) should be used to connect
thermostat to unit.
POWER AND CONTROL WIRING
Field wiring to the unit must conform to provisions of the National
Electrical Code, ANSI / NFPA No. 70 (in U.S.A.), current Canadian
Electrical Code C22.1 (in Canada) and/or local ordinances. The
unit must be electrically grounded in accordance with NEC and
CEC (as specified above) and/or local codes. Voltage tolerances
which must be maintained at the compressor terminals during
starting and running conditions are indicated on the unit Rating
Plate and the Unit Application Data table.
replacement wire must be of the type shown on the wiring
diagram and the same minimum gauge as the replaced wire.
Electrical line must be sized properly to carry the load. Use
copperconductors only. Each unit must be wired with a
separate branch circuit fed directly from the meter panel and
properly fused.
CAUTION: When connecting electrical power and control
wiring to the unit, waterproof type connectors
MUST BE USED so that water or moisture cannot
be drawn into the unit during normal operation. The
above waterproofing conditions will also apply
when installing a field-supplied disconnect switch.
Refer to the Typical Field Wiring figure and to the appropriate
unit wiring diagram for control circuit and power wiring
information.
TABLE 2 - CONTROL WIRE SIZES
Wire Size1 AWG. Gauge
The internal wiring harness furnished with this unit is an integral
part of a ETL and CGA design certified unit. Field alteration to
comply with electrical codes should not be required.
A fused disconnect switch should be field provided for the unit.
The switch must be separate from all other circuits. Wire entry
at knockout openings require conduit fittings to comply with
NEC (in U.S.A.), CEC (in Canada) and/or local codes. Refer to
the Dimensions and Clearnaces Figure for installation location.
If any of the wire supplied with the unit must be replaced,
Unitary Products Group
22
20
19
18
16
40
120
150
190
305
Maximum Wire Length2 Feet
Notes:
1. Solid, Class II copper wire
2. Based on a voltage drop of 1.2 volts per wire.
3. Total wire length is from unit to room thermostat, and back to unit
5
530.18-N6Y
TABLE 3 - GAS HEAT APPLICATION DATA
Input Capacity (Mbh)
0 To
2,000 Feet
Above
Sea Level
2,000 To
4,500 Feet
Above
Sea Level1
Max.
Min.
Max.
300
150
270
400
200
360
Output Capacity (Mbh)
0 To
2,000 Feet
Above
Sea Level
2,000 To
4,500 Feet
Above
Sea Level1
Min.
Max.
Max.
135
240
180
320
Temp.
Rise °F
At
Full Input 3
Available
on Models
Gas
Rate2
(Ft.3/Hr.)
Min.
Max.
213
15 & 20 Ton
279
20
50
281
15 & 20 Ton
372
30
60
NOTE: Heaters are shipped available for natural gas, but can be converted to
L.P. / Propane with Kit Model No. 1NP0418.
1
MBH rating should be reduced at the rate of 4 percent for each 1,000 feet above 4,500 feet.
2
Based on maximum input and 1075 Btu/Ft3.
3
The air flow must be adjusted to obtain a temperature rise within the range shown.
COMBUSTION DISCHARGE
The products of combustion are discharged horizontally
through two screened (hooded) openings on the upper gas
heat access panel.
GAS PIPING
Proper sizing of gas piping depends on the cubic feet per hour of
gas flow required, specific gravity of the gas and the length of run.
“National Fuel Gas Code” Z223.1 (in U.S.A.) or the current Gas
Installation Codes CAN/CGA-B149.1 and .2 (in Canada) should
be followed in all cases unless superseded by local codes or gas
utility requirements. Refer to the Pipe Sizing table.
The heating value of the gas may differ with locality. The value
should be checked with the local gas utility.
NOTE: There may be a local gas utility requirement specifying
a minimum diameter for gas piping. All units require a
one-inch pipe connection at the entrance fitting.
TABLE 4 - PIPE SIZING
Length in Feet
10
20
30
40
50
60
70
80
90
100
Nominal Iron Pipe Size
1 in.
1-1/4 in.
1,050
520
730
350
590
285
500
245
440
215
400
195
370
180
350
170
320
160
305
150
Maximum capacity of pipe in cubic feet of gas per hour. (Based upon a pressure drop of 0.3
inch water column and 0.6 specific gravity gas).
FIG. 6 - EXTERNAL SUPPLY CONNECTION
EXTERNAL SHUT-OFF
GAS CONNECTION
The gas supply line can be routed through the knockouts located on
the front of the unit or through the opening provided in the unit’s base.
Refer to the Dimensions and Clearances figure to locate these access
openings. Typical supply piping arrangements are shown in the
figures on this page. All shaded items are field-supplied.
If gas supply line is routed through the unit’s base ensure that
the burner assembly can be removed for maintenance without
disturbing the supply line. The supply piping and fittings must
6
lie below the bottom gas manifold to avoid interference with the
burner assembly.
Two grommets are shipped in the blower compartment (in parts
bag taped to the blower housing) of every unit with gas heat
and should be used in the knockouts when the gas piping
penetrates the front of the unit.
After the gas supply piping has been installed, the bottom
opening in the unit should be sealed to prevent water from
leaking into the building.
Gas piping recommendations:
1. A drip leg and a ground joint union must be installed in the
gas piping.
2. When required by local codes, a manual shut-off valve may
have to be installed outside of the unit.
3. Use wrought iron or steel pipe for all gas lines. Pipe
compound should be applied sparingly to male threads
only.
WARNING: Natural gas may contain some propane. Propane,
being an excellent solvent, will quickly dissolve
white lead or most standard commercial
compounds. Therefore, a special pipe compound
must be applied when wrought iron or steel pipe is
used. Shellac base compounds such as Gaskolac
or Stalastic, and compounds such as Rectorseal
#5, Cyde’s or John Crane may be used.
4. All piping should be cleaned of dirt and scale by hammering
on the outside of the pipe and blowing out the loose dirt and
scale. Before initial start-up, be sure that all of the gas lines
external to the unit have been purged of air.
5. The gas supply should be a separate line and installed in
accordance with all safety codes as prescribed under
“Limitations”. After the gas connections have been
completed, open the main shut-off valve admitting normal
gas pressure to the mains. Check all joints for leaks with
soap solution or other material suitable for the purpose.
NEVER USE A FLAME.
6. The furnace and its individual manual shut-off valve must
be disconnected from the gas supply piping system during
any pressure testing of that system at test pressures in
excess of 1/2 psig (3.48kPa).
The furnace must be isolated from the gas supply piping
system by closing its individual manual shut-off valve during
any pressure testing of the gas supply piping system at test
pressures equal to or less than 1/2 psig (3.48kPa).
7. A 1/8 inch NPT plugged tapping, accessible for test gage
connection, must be installed immediately upstream of the
gas supply connection to the furnace.
FIG. 7 - BOTTOM SUPPLY CONNECTION
EXTERNAL SHUT-OFF
L.P. UNITS, TANKS AND PIPING
All gas heat units are shipped from the factory equipped for
natural gas use only. The unit may be converted in the field for
use with L.P./propane gas with accessory kit model number
1NP0418.
Unitary Products Group
530.18-N6Y
VENT AND COMBUSTION AIR HOODS
Two vent hoods and a combustion air hood (with screens) are
shipped attached to the blower housing in the blower
compartment. These hoods must be installed to assure proper
unit function. All hoods must be fastened to the outside of the
gas heat access panel with the screws provided in the bag also
attached to the blower housing.
VENT AIR
OUTLET
HOODS
SLOTTED
OPENINGS IN
ACCESS PANEL
The screen for the combustion air intake hood is secured to the
inside of the access panel opening with four fasteners and the
screws used for mounting the hood to the panel. The top flange
of this hood slips in under the top of the access panel opening
when installing. Refer to Vent and Combustion Air Hood figure.
Each vent hood is installed by inserting the top flange of the
hood into the slotted opening in the access panel and securing
in place.
OPTIONAL ECONOMIZER/MOTORIZED DAMPER
RAIN HOOD
COMBUSTION
AIR INTAKE
HOOD
GAS HEAT
ACCESS
PANELS
The instruction for the optional economizer/motorized damper
rain hood can be found in form 44-320-2. Use these instructions
when field assembling an economizer rain hood onto a unit.
The outdoor and return air dampers, the damper actuator, the
damper linkage, the outdoor and return air divider baffles, and
all the control sensors are factory mounted as part of the
“Factory installed” economizer option.
ENTHALPY SET POINT ADJUSTMENT
Remove the economizer access panel from the unit to check
the following adjustments. Loosen but do not remove the two
panel latches.
FIG. 8 - VENT AND COMBUSTION AIR HOODS
All L.P./propane gas equipment must conform to the safety
standards of the National Fire Protection Association.
For satisfactory operation, L.P./propane gas pressure must be
8.8 inch W.C at the unit under full load. Maintaining proper gas
pressure depends on three main factors:
1. The vaporization rate which depends on (a) the
temperature of the liquid and (b) the “wetted surface” area
of the container or containers.
2. The proper pressure regulation. (Two-stage regulation is
recommended from the standpoint of both cost and
efficiency.)
3. The pressure drop in the lines between regulators and
between the second stage regulator and the appliance.
Pipe size required will depend on the length of the pipe run
and the total load of all appliances.
Complete information regarding tank sizing for vaporization,
recommended regulator settings, and pipe sizing is available
from most regulator manufacturers and L.P./propane gas
suppliers.
L.P./propane gas is an excellent solvent and special pipe
compound must be used when assembling piping for this gas
as it will quickly dissolve white lead or most standard
commercial compounds. Shellac base compounds such as
Rectorseal #5 are satisfactory for this type of gas.
Check all connections for leaks when piping is completed,
using a soap solution. NEVER USE A FLAME.
Unitary Products Group
CAUTION: Extreme care must be exercised in turning both the
setpoint and minimum position adjusting screws to
prevent twisting them off.
6. The enthalpy set point may now be set by selecting the desired
setpoint shown in the Adjsuting Enthalpy Setpoint figure. Adjust
as follows:
• For a single enthalpy operation, carefully turn the set
point adjusting screw to the “A”, “B”, “C” or “D” setting
corresponding to the lettered curve.
• For a dual enthalpy operation, carefully turn the set point
adjusting screw fully clockwise past the “D” setting.
7. To check that the damper blades move smoothly without
binding, carefully turn the minimum position adjusting
screw fully clockwise and then energize and de-energize
terminals “R” to “G”. With terminals “R” to “G” energized,
turn the minimum position screw counterclockwise until the
desired minimum position has been attained.
8. Replace the economizer access panel. Reposition the two
latches horizontally and retighten the screws.
POWER EXHAUST/BAROMETRIC RELIEF DAMPER
AND RAIN HOOD OPTION
The instructions for the power exhaust/barometric relief
damper and rain hood can be found in form 44-320-10. The
exhaust fan, all supporting brackets, angles, and the wiring are
factory installed as part of the power exhaust option.
All of the components, including the dampers, hardware, and
mounting instructions are shipped in a single package external
from the unit. The hood must be field assembled and installed.
Power exhaust is not available as a field installed option.
7
530.18-N6Y
FIG. 9 - ENTHALPY SETPOINT ADJUSTMENT
8
Unitary Products Group
530.18-N6Y
TABLE 5 - PHYSICAL DATA
UNIT SIZE
15 TON 20 TON
EVAPORATOR CENTRIFUGAL BLOWER (Dia. x Wd. in.) 15 x 15 18 x 15
BLOWER
FAN MOTOR HP
5
7.5
ROWS DEEP
3
3
EVAPORATOR
FINS PER INCH
13.5
13.5
COIL
FACE AREA (Sq. Ft.)
15.5
20.0
30
30
CONDENSER PROPELLER DIA. (in.) (Each)
FAN
FAN MOTOR HP
(Each)
1
1
(Two Per Unit) NOM. CFM TOTAL
(Each)
6500
7200
ROWS DEEP
2
2
CONDENSER
FINS PER INCH
13
20
COIL
FACE AREA (Sq. Ft.)
36.0
43.3
1*
2
COMPRESSOR 10-TON TANDEM
(Qty. Per Unit) 5-TON HERMETIC
1
QUANTITY PER UNIT (16" X 20" X 2")
4
QUANTITY PER UNIT (16" X 25" X 2")
4
AIR
FILTERS
QUANTITY PER UNIT (18" X 24" X 2")
5
TOTAL FACE AREA (sq. ft.)
15.0
20.0
17/8
18/0
REFRIGERANT 22 SYSTEM NO. 1
CHARGE
(lbs./oz.)
SYSTEM NO. 2
8/8
18/0
MODELS
OPERATING WEIGHTS (LBS.)
240 Mbh
Basic Unit
320 Mbh
Economizer
Economizer with
Options
Power Exhaust
Motorized Damper
Roof Curb
Accessories Barometric Damper
Wood Skid
15 TON 20 TON
2100
2300
2140
2340
160
245
150
175
45
200
185
45
220
*This compressor will be energized first.
Unitary Products Group
9
530.18-N6Y
TABLE 6 - ELECTRICAL DATA
COMPRESSORS
MODEL
POWER
SUPPLY
#1
#2
RLA LRA RLA LRA
DCG180
DCG240
208/230-3-60
460-3-60
575-3-60
208/230-3-60
460-3-60
575-3-60
38.4
19.2
15.4
38.4
19.2
15.4
248
124
100
248
124
100
19.2
9.6
7.7
38.4
19.2
15.4
124
62
50
248
124
100
COND. FAN
MOTORS
(#1 & #2)
HP
FLA
EACH
EACH
1
4.1 / 4.2
1
2.1
1
2.0
1
4.1 / 4.2
1
2.1
1
2.0
SUPPLY AIR
BLOWER
MOTOR
HP
FLA
MINIMUM
CIRCUIT
AMPACITY
(AMPS)
5
5
5
7.5
7.5
7.5
15.4 / 14.4
7.2
5.9
21.0 / 19.4
9.7
7.8
87.1 / 84.9
42.4
33.9
115.1 / 111.6
55.8
44.8
MAXIMUM
TIME DELAY
FUSE SIZE
(AMPS)
100
50
40
125
60
50
VOLTAGE
POWER SUPPLY
VOLTAGE
LIMITATIONS**
MIN.
MAX.
208/230-3-60
187
253
460-3-60
414
506
575-3-60
518
630
**Utilization Range “A” in accordance with ARI Standard 110.
10
Unitary Products Group
530.18-N6Y
B L O W E R
A C C E S S
F IE L D -S U P P L IE D
D IS C O N N E C T S W IT C H
L O C A T IO N
B L O W E R M O T O R
A C C E S S
B L O
C O M
A C C
(A u x
E C
F IX
P O
(S e
O N
E D
W E
e d
W E R
P A R T M E N T
E S S
ilia r y )
O M IZ E
O U T D
R E X H
e ta il " Y
R / M O T O R IZ E D D A M P E
O O R IN T A K E A IR A N D
A U S T R A IN H O O D S
")
C
A
(S
R ,
RETURN AIR
O M P R E S S O R
C C E S S
e e d e ta il " X " )
SUPPLY AIR
O P T IO N A L
C O IL G U A R D
D O T P L U G
(F o r p re s s u re
D r o p R e a d in g )
4 8 -5 /8 " (1 5 T O N )
5 2 -5 /8 " (2 0 T O N )
CONDENSER AIR
G A S H E A T
A C C E S S
OUTDOOR AIR
C O N D E N S E R
C O IL S
V E N T A IR
O U T L E T
H O O D S
(Economizer)
2 1 "
5 "
7 -1 /8 "
C O M B U S T IO N
A IR IN L E T
H O O D
1 2 5 -1 /4 " (1 5 T O N )
1 3 6 -1 /4 " (2 0 T O N )
All dimensions are in inches. They are subject to change without notice. Certified dimensions will be provided upon request.
6 -3 /8 "
9 -3 /4 "
(C )
G A S S U P P L Y
E N T R Y
9 2 "
5 -7 /8 "
(A )
C O N T R O L W IR IN G
E N T R Y
4 6 -5 /8 "
C O N T R O L B O X
A C C E S S
F R O N T
V IE W
1 1 -1 /2 "
3 5 "
B O T T O
A N D
A IR O
(S e
1 2 -1 /4 " (1 5 T O N )
3 5 -1 /4 " (2 0 T O N )
M
R E
P E
e N
UTILITIES ENTRY DATA
(B )
P O W E R W IR IN G
E N T R Y
S U P P L Y
T U R N
N IN G S
o te )
HOLE
R E T U R N
A IR
3 -3 /4 "
3 3 "
S U P P L Y
A IR
2 -3 /4 "
A
2 1 -1 /2 "
1 1 -1 /8 "
B
U N
S h
B o
a n
lo c
IT B A
o w n s
tto m D
d G a s
a t io n s
S E W
e p a ra
u c t o
P ip in
IT H
te ly
p e n
g C
R A IL
to illu
in g s ,
o n n e c
S
s tra te
P o w e r
tio n
(B )
P O W E R W IR IN G
E N T R Y
(D )
G A S S U P P L Y
E N T R Y
8 -1 /8 "
N O
F o r
d im
s u p
T E
c u
e n
p ly
:
r b m o u n te d u n its , r e fe r to th e c u r b h a n g e r
s io n s o f t h e c u r b f o r t h e p r o p e r s iz e o f th e
a n d r e tu r n a ir d u c t c o n n e c tio n s .
C
D
(A )
C O N T R O L W IR IN G
E N T R Y
DUCT COVERS - Units are shipped with the bottom
duct openings covered. An accessory flange kit is available for connecting side ducts.
For bottom duct applications:
1. Remove the side panels from the supply and return
air compartments to gain access to the bottom
supply and return air duct covers.
2. Remove and discard the bottom duct covers. (Duct
openings are closed with sheet metal covers except
when the unit includes a power exhaust option. The
covering consists of a heavy black paper composition.)
3. Replace the side supply and return air compartment
panels.
For side duct applications;
1. Replace the side panels on the supply and return air
compartments with the accessory flange kit panels.
2. Connect ductwork to the duct flanges on the rear of
the unit.
E C O
M O T
D A M
R A IN
(o n O
P O W E R E X H A U S T
R A IN H O O D
( o n R e tu r n A ir C o m p a r tm e n t)
N O M IZ E R
O R IZ E D
P E R
H O O D
u td o o r A ir C o m p a r tm e n t)
E C O N O M IZ E R / M O T O R IZ E D D A M P E R
A N D P O W E R E X H A U S T R A IN H O O D S
F IX E
O U T
IN T A
( lo c a
R e tu
C o m
3 4 -1 /4 "
2 "
6 6 -1 /2 "
R E A R
L H
V IE W
Front
Back
Left Side (Filter Access)
Right Side (Cond. Coil)
Below Unit1
F IL T E R
A C C E S S
Above Unit2
S U P P L Y
A IR
R E T U R N
A IR
1 " N P T F E M A L E
C O N D . D R A IN
C O N N E C T IO N
4 0 -1 /2 "
R E A R
V IE W
2 7 -3 /4 "
5 -1 /8 "
O U T D O O R A IR
C O M P A R T M E N T
A C C E S S
2 8 -5 /8 " (1 5 T o n s )
3 9 -5 /8 " (2 0 T o n s )
DETAIL “X” (ACCESSORY SIDE SUPPLY AND RETURN AIR OPENINGS)
FIG. 10 - DIMENSIONS & CLEARANCES - 15 & 20 TON
Unitary Products Group
36"
24" (Less Economizer)
49" (With Economizer)
24" (Less Economizer)
36"3 (With Economizer)
36"
20"
72" With 36" Maximum
Horizontal Overhang
(For Condenser Air
Discharge Outlet)
1Units (applicable in U.S.A. only) may be installed on combustible floors
made from wood or class A, B or C roof covering material.
2
Units must be installed oudoors. Overhanging structures or shrubs should
not obstruct condenser air discharge outlet.
3
If economizer is factory installed, the assembled hood kit must be removed
prior to final installation. This hood is 54" long.
NOTE:
A one-inch clearance must be provided between any combustible material
and the supply air ductwork for a distance of 3 feet from the unit.
1 8 -5 /8 "
R E T U R N A IR
A C C E S S
V IE W
CLEARANCES
4 0 -3 /8 "
S U P P L Y A IR
A C C E S S
9 2 "
3 6 -1 /4 "
D E T A IL "Y "
U N IT W IT H R A IN H O O D S
D O T P L U G
(F o r p re s s u re
d r o p r e a d in g )
O U T D O O R
A IR
1 " C O N D E N S T A T E
D R A IN
(M u s t b e tra p p e d )
5 "
3 6 "
E V A P O R A T O R
S E C T IO N
C O M P R E S S O R
A C C E S S
D
D O O R A IR
K E H O O D
te d o n
r n A ir
p a rtm e n t)
1 6 -1 /8 "
C O N D E N S E R S E C T IO N
5 -1 /2 "
Control Front
Wiring
Bottom
Front
Power
Wiring
Bottom
Gas Piping (Front)
Gas Piping (Bottom)*
9 -3 /4 "
S U P P L Y A IR
C O M P A R T M E N T
G A U G E L IN E
A C C E S S
USED FOR
*Opening in the bottom of the unit can be located by the slice
in the insulation.
4 6 -5 /8 "
9 -1 /4 "
1 2 -1 /2 "
OPENING
SIZE
(DIA.)
1-1/8" KO
3/4" NPS (Fem.)
3-5/8" KO
3" NPS (Fem.)
2-3/8" KO
1-11/16" Hole
The products of combustion must not be allowed to accumulate within a
confined space and recirculate.
Locate unit so that the vent air outlet hoods are at least:
•
•
•
Three (3) feet above any forced air inlet located within 10 horizontal feet
(excluding those integral to the unit).
Four (4) feet below, 4 horizontal feet from, or 1 foot above any door or gravity
air inlet into the building.
Four (4) feet from electric meters, gas meters, regulators and relief equip-
11
530.18-N6Y
B
E
F
C
A
D
A
FRONT
C
FRONT
D
4 POINT LOADS
B
6 POINT LOADS
FIG. 11 - FOUR AND SIX POINT LOADS
TABLE 7 - FOUR AND SIX POINT LOADS
UNIT
TOTAL
2300
2500
180
240
A
539
538
4 - POINT LOADS (LBS)
B
563
563
C
612
715
D
586
684
NOTE: These weights are with economizer, and the largest blower motor available.
UNIT
180
240
TOTAL
2300
2500
A
351
334
B
367
350
6 - POINT LOADS (LBS)
C
D
392
416
426
502
E
399
481
F
375
407
NOTE: These weights are with economizer and the largest blower motor available.
CENTER OF GRAVITY
12
Unitary Products Group
530.18-N6Y
TABLE 8 - SUPPLY AIR BLOWER PERFORMANCE (15 TON)
DCG180 - BOTTOM DUCT CONNECTIONS
BLOWER
SPEED,
(RPM)
MOTOR
PULLEY
(TURNS
OPEN)*
4500
ESP
BHP
CFM
6000
5250
6750
7200
KW
ESP
BHP
KW
ESP
BHP
KW
ESP
BHP
KW
ESP
BHP
KW
2.1
2.2
2.4
2.5
2.6
2.7
2.9
0.6
0.7
0.8
0.9
1.0
1.1
1.3
2.9
3.0
3.1
3.2
3.4
3.6
3.8
2.6
2.7
2.8
2.9
3.0
3.2
3.4
0.3
0.4
0.5
0.6
0.7
0.8
1.0
3.4
3.5
3.6
3.7
3.8
4.0
4.4
3.0
3.1
3.2
3.3
3.4
3.6
3.9
0.2
0.4
0.5
0.6
0.8
4.1
4.4
4.5
4.7
5.0
3.7
3.9
4.0
4.2
4.5
0.2
0.3
0.4
0.6
5.0
5.1
5.4
5.6
4.5
4.6
4.8
5.0
0.9
1.0
1.2
1.4
1.7
1.9
3.2
3.4
3.6
3.9
4.4
4.7
2.9
3.0
3.2
3.5
3.9
4.2
0.6
0.7
0.9
1.1
1.4
1.6
3.7
3.8
4.1
4.5
5.0
5.5
3.3
3.4
3.7
4.0
4.5
4.9
0.4
0.5
0.7
0.9
1.2
-
4.4
4.5
4.8
5.1
5.8
-
3.9
4.0
4.3
4.6
5.2
-
0.2
0.3
0.4
-
5.0
5.1
5.5
-
4.5
4.6
4.9
-
0.7
0.8
0.9
1.0
1.1
1.2
1.4
3.0
3.1
3.2
3.4
3.6
3.7
3.9
2.7
2.8
2.9
3.0
3.2
3.3
3.5
0.4
0.5
0.6
0.7
0.8
0.9
1.1
3.5
3.6
3.7
3.8
4.0
4.2
4.5
3.1
3.2
3.3
3.4
3.6
3.8
4.0
0.2
0.4
0.5
0.6
0.7
0.9
4.1
4.4
4.5
4.7
4.9
5.1
3.7
3.9
4.0
4.2
4.4
4.6
0.2
0.3
0.4
0.5
-
5.0
5.1
5.4
5.7
-
4.5
4.6
4.8
5.1
-
3.0
3.4
3.5
3.9
4.2
4.3
0.7
1.0
1.1
1.4
1.6
1.7
3.8
4.4
4.5
5.0
5.5
5.6
3.4
3.9
4.0
4.5
4.9
5.0
0.5
0.8
0.9
1.2
-
4.5
5.0
5.1
5.8
-
4.0
4.5
4.6
5.2
-
0.3
0.6
-
5.1
5.6
-
4.6
5.0
-
208 VOLT AND STANDARD DRIVE
850
870
915
965
980
1010
1040
6.0**
5.5
4.5
3.5
3.0
2.0
1.0
0.9
1.0
1.1
1.2
1.3
1.4
1.6
2.4
2.5
2.6
2.7
2.9
3.0
3.2
208 VOLT AND HIGH SPEED DRIVE ACCESSORY
965
980
1025
1065
1125
1170
6.0
5.5
4.5
3.5
2.0
1.0
1.2
1.3
1.4
1.6
1.9
2.1
2.7
2.9
3.1
3.4
3.6
3.9
2.5
2.6
2.8
3.0
3.2
3.5
230/460 VOLT AND STANDARD DRIVE
870
915
965
980
1015
1050
1065
6.0**
5.0
4.0
3.5
2.5
1.5
1.0
1.0
1.1
1.2
1.3
1.4
1.5
1.6
2.5
2.6
2.7
2.9
3.0
3.1
3.4
2.2
2.4
2.5
2.6
2.7
2.8
3.0
230/460 VOLT AND HIGH SPEED DRIVE ACCESSORY
980
1045
1065
1125
1170
1190
6.0
4.5
4.0
2.5
1.5
1.0
1.3
1.6
1.7
1.9
2.1
2.2
2.9
3.2
3.4
3.6
3.9
4.0
2.6
2.9
3.0
3.2
3.5
3.6
1.0
1.3
1.4
1.7
1.8
1.9
3.4
3.8
3.9
4.4
4.7
4.8
NOTES: 1. Blower performance includes a gas-fired heat exchanger, fixed outdoor air, two-inch T/A filters and a dry evaporator coil.
2. Refer to the additional Static Resistances table.
ESP = External Static Pressure available for the supply and return air duct system. All internal unit resistances have been deducted from the total static pressure of the blower.
* Do NOT close the pulley below 1 turn open.
** Factory setting.
Unitary Products Group
13
530.18-N6Y
TABLE 9 - SUPPLY AIR BLOWER PERFORMANCE (20 TON)
DCG240 - BOTTOM DUCT CONNECTIONS
BLOWER
SPEED,
(RPM)
MOTOR
PULLEY
(TURNS
OPEN)*
6000
ESP
BHP
CFM
8000
7000
9000
9400
KW
ESP
BHP
KW
ESP
BHP
KW
ESP
BHP
KW
ESP
BHP
KW
3.0
3.2
3.4
3.6
3.8
3.9
4.0
0.7
0.9
1.1
1.3
1.5
1.6
1.7
4.3
4.7
5.0
5.1
5.4
5.5
5.7
3.7
4.0
4.2
4.3
4.5
4.7
4.8
0.2
0.4
0.6
0.8
1.0
1.1
1.2
5.1
5.6
5.9
6.0
6.3
6.4
6.6
4.3
4.7
5.0
5.1
5.3
5.4
5.6
0.1
0.2
0.4
0.5
0.7
6.7
6.9
7.2
7.5
7.8
5.7
5.8
6.1
6.3
6.6
0.1
0.2
-
8.5
8.6
-
7.1
7.3
-
1.3
1.5
1.6
1.8
2.0
2.1
2.3
5.1
5.4
5.5
5.8
6.1
6.3
6.8
4.3
4.5
4.7
4.9
5.1
5.3
5.7
0.8
1.0
1.1
1.3
1.4
1.5
1.8
6.0
6.3
6.4
6.7
7.1
7.3
7.9
5.1
5.3
5.4
5.7
6.0
6.2
6.6
0.2
0.4
0.5
0.7
0.9
1.0
-
6.9
7.2
7.5
8.0
8.4
8.6
-
5.8
6.1
6.3
6.7
7.0
7.2
-
0.1
0.2
-
8.5
8.6
-
7.1
7.3
-
0.7
0.9
1.1
1.3
1.5
1.6
1.7
1.8
4.3
4.7
5.0
5.1
5.4
5.5
5.7
5.8
3.7
4.0
4.2
4.3
4.5
4.7
4.8
4.9
0.2
0.4
0.6
0.8
1.0
1.1
1.2
1.3
5.1
5.6
5.9
6.0
6.3
6.4
6.6
6.7
4.3
4.7
5.0
5.1
5.3
5.4
5.6
5.7
0.1
0.2
0.4
0.5
0.6
0.7
6.7
6.9
7.2
7.5
7.8
8.0
5.7
5.8
6.1
6.3
6.6
6.7
0.1
0.2
-
8.5
8.6
-
7.1
7.3
-
4.3
4.5
4.7
4.8
4.9
5.1
5.3
5.7
5.9
0.8
1.0
1.1
1.2
1.3
1.4
1.5
1.8
1.9
6.0
6.3
6.4
6.6
6.7
7.1
7.3
7.9
8.3
5.1
5.3
5.4
5.6
5.7
6.0
6.2
6.6
6.9
0.2
0.4
0.5
0.6
0.7
0.9
1.0
-
6.9
7.2
7.5
7.8
8.0
8.4
8.6
-
5.8
6.1
6.3
6.6
6.7
7.0
7.2
-
0.1
0.2
-
8.5
8.6
-
7.1
7.3
-
208 VOLT AND STANDARD DRIVE
870
900
930
950
980
995
1015
6.0**
5.0
4.0
3.0
2.0
1.5
1.0
1.3
1.4
1.6
1.7
1.9
2.1
2.2
3.6
3.8
4.1
4.2
4.5
4.6
4.8
208 VOLT AND HIGH SPEED DRIVE ACCESSORY
950
980
995
1025
1050
1065
1100
6.0
5.0
4.5
3.5
2.5
2.0
1.0
1.7
1.9
2.1
2.3
2.5
2.6
2.9
4.2
4.5
4.6
4.9
5.1
5.3
5.6
3.6
3.8
3.9
4.1
4.3
4.4
4.7
230/460 VOLT AND STANDARD DRIVE
870
900
930
950
965
995
1015
1025
6.0**
5.0
4.0
3.5
2.5
2.0
1.5
1.0
1.3
1.4
1.6
1.7
1.9
2.1
2.2
2.3
3.6
3.8
4.1
4.2
4.5
4.6
4.8
4.9
3.0
3.2
3.4
3.6
3.8
3.9
4.0
4.1
230/460 VOLT AND HIGH SPEED DRIVE ACCESSORY
950
980
995
1015
1025
1050
1065
1100
1120
6.0
5.0
4.5
4.0
3.5
3.0
2.5
1.5
1.0
1.7
1.9
2.1
2.2
2.3
2.5
2.6
2.9
3.1
4.2
4.5
4.6
4.8
4.9
5.1
5.3
5.6
5.8
3.6
3.8
3.9
4.0
4.1
4.3
4.4
4.7
4.9
1.3
1.5
1.6
1.7
1.8
2.0
2.1
2.3
2.5
5.1
5.4
5.5
5.7
5.8
6.1
6.3
6.8
7.0
NOTES: 1. Blower performance includes a gas-fired heat exchanger, fixed outdoor air, two-inch T/A filters and a dry evaporator coil.
2. Refer to the additional Static Resistances table.
ESP = External Static Pressure available for the supply and return air duct system. All internal unit resistances have been deducted from the total static pressure of the blower.
* Do NOT close the pulley below 1 turn open.
** Factory setting.
14
Unitary Products Group
530.18-N6Y
TABLE 10 - STATIC RESISTANCES*
EXTERNAL STATIC PRESSURE DROP
RESISTANCE, IWG
CFM
DESCRIPTION
15 TON
4500
6000
7200
6000
WET COIL
0.1
0.1
0.1
0.1
ECONOMIZER OPTION
0.1
0.1
0.1
0.1
HORIZONTAL DUCT CONNECTIONS
0.2
0.3
0.5
0.2
20 TON
8000
0.1
0.1
0.3
9400
0.1
0.1
0.5
*Deduct these resistance values from the available unit ESP values listed in the respective blower performance table except for Horizontal Duct Connections
(Shaded
). Add these values due to less airflow resistance.
TABLE 11 - POWER EXHAUST PERFORMANCE
MOTOR
SPEED
HIGH*
MEDIUM
LOW
0.2
CFM
5250
4900
4400
KW
0.83
0.77
0.72
STATIC RESISTANCE OF RETURN DUCTWORK, IWG
0.3
0.4
0.5
CFM
KW
CFM
KW
CFM
KW
4500
0.85
4200
0.88
3750
0.93
3900
0.79
3500
0.82
2900
0.85
3700
0.74
3000
0.78
-
0.6
CFM
3000
-
KW
0.99
-
*Factory Setting
Power Exhaust motor is a 3/4 HP, PSC type with sleeve bearings, a 48 frame and inherent protection.
TABLE 12 - BLOWER MOTOR AND DRIVE DATA
ADJUSTABLE MOTOR PULLEY
MOTOR1
BLOWER
MODEL
DRIVE RANGE
OUTSIDE PITCH
SIZE
BORE
(RPM) HP FRAME EFF. DESIGDIA.
DIA.
(IN.)
(%) NATION
(IN.)
(IN.)
Stan850/1065
dard
4.315 TON High
5
184T
83
1VP56
5.35
1-1/8
5.32
Speed 965/1190
Access
Stan870/1025
dard
5.520 TON High
7.5 213T
89
1VP68
6.75
1-3/8
6.52
Speed 950/1120
Access
BELT
(NOTCHED)
PITCH
OUTSIDE PITCH
BORE DESIGDESIGDIA.
LENGTH QTY.
DIA.
(IN.) NATION
NATION
(IN.)
(IN.)
(IN.)
FIXED BLOWER PULLEY
BK90
8.75
8.4
1
BX70
71.8
1
BK80
7.75
7.4
1
BX68
69.8
1
BK120
11.75
11.4 1-3/16 BX83
84.8
1
BK110
10.75
10.4 1-3/16 BX81
81.8
1
1All motors have a nominal speed of 1800 RPM, a 1.15 service factor and a solid base. They can operate to the limit of their service factor because they are located in the moving air, upstream
of any heating device.
2 Do NOT close this pulley below 1 turn open.
Unitary Products Group
15
530.18-N6Y
OPERATION
COOLING SYSTEM
The cooling section is a complete factory package utilizing an
air-cooled condenser. The system is factory-charged with
Refrigerant-22.
The compressors are hermetically sealed, internally sprung
and base mounted with rubber insulated hold-down bolts.
Compressors have inherent (internal protection. If there is an
abnormal temperature rise in compressor, the protector will
open to shut down the compressor.
PRELIMINARY OPERATION COOLING
After installation has been completed, energize the crankcase
heaters for at lest four hours before operation the unit. After the
initial installation, the compressors should be given three false
starts (energized just long enough to make a few revolutions
with 5-7 minutes delay between each start, before being put
into full time service.
COOLING SEQUENCE OF OPERATION
NO OUTDOOR AIR OPTIONS - When the room thermostat
calls for “first-stage” cooling, the low voltage control circuit from
“R” to “G” and “Y1" is completed to energize compressor #1,
condenser fan motor #1, condenser fan motor #2 (if the ambient
temperature is above 60°F), and the supply air blower motor (if
the fan switch on the room thermostat is set in the ”AUTO"
position).
When the thermostat calls for “second-stage” cooling, the low
voltage control circuit from “R” to “Y2" is completed to energize
compressor #2.
After the thermostat is satisfied and opens, all components will
stop simultaneously. The blower motor will continue to operate
if the fan switch on the room thermostat is set in the “ON”
position.
ECONOMIZER WITH SINGLE ENTHALPY SENSOR - When
the room thermostat calls for “first-stage” cooling, the low
voltage control circuit from “R” to “G” and “Y1" is completed.
The ”R" to “G” circuit energizes the blower motor (if the fan
switch on the room thermostat is set in the “AUTO” position)
and drives the economizer dampers from fully closed to their
minimum position. If the enthalpy of the outdoor air is below the
setpoint of the enthalpy controller (previously determined), “Y1"
energizes the economizer. The dampers will modulate to
maintain a constant supply air temperature as monitored by the
discharge air sensor. If the outdoor air enthalpy is above the
setpoint, ”Y1" energizes compressor #1, condenser fan motor
#1, and condenser fan motor #2 (if the ambient temperature is
above 60°F).
When the thermostat calls for “second-stage” cooling, the low
voltage control circuit from “R” to “Y2" is completed. If the
enthalpy of the outdoor air is below the setpoint of the enthalpy
controller (i.e. first stage has energized the economizer), ”Y2"
will energize compressor #1. If the outdoor air is above the
setpoint, “Y2" will energize compressor #2.
After the thermostat is satisfied and opens, all components will
stop simultaneously. The blower motor will continue to operate
if the fan switch on the room thermostat is set in the “ON”
position.
ECONOMIZER WITH DUAL ENTHALPY SENSORS - The
operation with the dual enthalpy sensors is identical to the
single sensor except that a second enthalpy sensor is mounted
in the return air. This return air sensor allows the economizer
to choose between outdoor air and return air, whichever has
the lowest enthalpy value, to provide maximum operating
efficiency.
16
ECONOM IZER (SINGLE OR DUAL) WITH POWER
EXHAUST - This system operates as specified above with one
addition. The power exhaust motor is energized whenever the
economizer is chosen by the enthalpy sensor for first stage
cooling, “Y1". As always, the ”R" to “G” connection provides
minimum position but does not provide power exhaust
operation.
MOTORIZED OUTDOOR AIR DAMPERS - This system
operation is the same as the units with no outdoor air options
with one exception. When the “R” to “G” circuit is complete, the
motorized damper drives open to a position set by the
thumbwheel on the damper motor. When the “R” to “G” circuit
is opened, the damper spring returns fully closed.
CONTINUOUS BLOWER - Continuous blower operation is
possible by closing the R to G circuit on the thermostat.
SAFETY CONTROLS
Each refrigerant system is equipped with the following safety
controls:
1. A Suction Line Freezestat to protect against low evaporator
temperatures due to a low air flow or a low return air
temperature. (Opens at 26°F +5° F and resets at 38°F +
5°F.)
2. A High Pressure Cutout Switch to protect against excessive
discharge pressures due to a blocked condenser coil or a
condenser motor failure. (Opens at 380 psig + 10 and resets
at 300 psig + 10.)
3. A Low Pressure Switch to protect against loss of refrigerant
charge. (Opens at 7 psiog + 3 and resets at 22 psig + 5.)
If either one of the above safety controls opens, that individual
refrigerant system will be locked out. The other refrigerant
system will continue in operation unless it too is effected by the
same fault. The lock out of either system can be reset by
opening the 24V circuit either at the room thermostat or at the
unit disconnect.
HEATING SYSTEM
The following sequence describes the operation of the gas heat
section.
CONTINUOUS BLOWER
With the room thermostat switch set to “ON”, the supply air
blower will operate continuously. The normally closed contact
“K5-1" provides 24 volt power to the “3M” contactor. The “3M-1,
2 & 3" power contacts close and the blower motor operates.
INTERMITTENT BLOWER
With the room thermostat system switch set to the “AUTO” or
“HEAT” position and the fan switch set to “AUTO”, the supply
air blower will operate after the room thermostat calls for heat
and the time delay relay closes.
The “TH1" closes, the heat relay ”RW1" is energized. The
“RW1-1” power contact closes energizing the line voltage draft
motor. The “RW1-2" contact is also closed. As the speed of the
draft motor reaches approximately 2500 RPM, the centrifugal
switch contact located on the end of the draft motor shaft closes
to power the first stage ignition module “IC1”.
Ignition module “IC1" will immediately start the first stage ignitor
sparking and will open the redundant valve located inside the
first stage main gas valve “GV1” to allow a flow of gas to only
the first stage carryover tube. Only after the pilot flame has been
ignited and the presence of pilot flame detected at the “IC1” by
a signal sent back through the flame sensor is sparking
terminated and the first stage main gas valve opened.
Gas flows into each of the main burners and is ignited from the
carryover tube flame.
If “IC1” fails to detect a pilot flame, it will continue to try for a
maximum of 85 seconds to ignite the pilot tube. If the pilot flame
is not detected, then “IC1" will lock out first stage furnace
Unitary Products Group
530.18-N6Y
operation until 24V power is removed from the module either
at the unit or by resetting the room thermostat.
At the same time power was supplied to the “RW1”, a parallel
circuit activates “ETD” which closes the “ETD” contact after
approximately 35 seconds and energizes “K5" which closes
”K5-2" and starts the blower by energizing “3M”.
When “TH2" closes, heat relay ”RW2" is energized. The
“RW2-1" contact is closed energizing the second stage ignition
module ”IC2". “IC2" will immediately start the second stage
ignitor sparking and will open the redundant valve located
inside the second stage main gas valve ”GV2" to allow a flow
of gas to the second stage carryover tube. Only after the pilot
flame has been ignited and the presence of pilot flame detected
at “IC2" by a signal sent back through the flame sensor is
sparking terminated and the main gas valve opened.
Gas flows into each of the second stage main burners and is
ignited from the carryover tube flame.
If “IC2" fails to detect a pilot flame, it will continue to try for a
maximum of 85 seconds to ignite the pilot tube. If the pilot flame
is not detected, then ”IC2" will lock out first stage furnace
operation until 24V power is removed from the module either
at the unit or by resetting the room thermostat. Note that the
second stage furnace can operate even if first stage has locked
out.
REDUNDANT
VALVE
4. Flame Sensor Rod / 100% Ignition Control Lock-Out. The
flame rods and controls are located per Proper Flame Adjustment figure. If an ignition control fails to detect a signal from
the flame sensor indicating the pilot flame is properly ignited,
then the main gas valve will not open. It will continue to try and
ignite the pilot for a maximum of 85 seconds, then if the pilot
flame is not detected, the ignition control will lock out furnace
operation until 24V power is removed from the module either
at the unit or by resetting the room thermostat.
5. Rollout Switch. This switch is located above the main burners in the control compartment which in the event of a
sustained main burner rollout shuts off and locks out both
ignition controls closing both gas valves. The ignition controls lock out furnace operation until 24V power is removed
from the controls either at the unit or by resetting the room
thermostat. Note the auto reset rollout switch must reset
before allowing furnace operation.
6. Auxiliary limit switch (AUX) - This control is located inside
the heat exchanger compartment and is set to open at
TABLE 13 - LIMIT CONTROL SETTING
Capacity, MBH
Input
Output
300
240
400
320
Units
(Tons)
15 & 20
15 & 20
Limit Control
Opens, °F
195
195
IG N . C O N T R O L # 2
MAIN VALVE
IG N . C O N T R O L # 1
GAS MAIN
R O L L O U T S W .
GAS
VALVE
TO PILOT BURNER
TO MAIN
BURNER
FIG. 12 - GAS VALVE PIPING
When the heating cycle is complete, “TH2" opens
de-energizing the ”RW2" then “TH1" opens de-energizing
”RW1" and “ETD”, thus closing all gas valves. The blower motor
will continue to run (approximately 45 seconds after the furnace
is shut down) until “ETD” opens, de-energizing the “K5" relay
and ”3M" contactor.
SAFETY CONTROLS
The control circuit includes the following safety controls:
1. Limit Control (LS). This control is located inside the heat
exchanger compartment and is set to open at the temperature indicated in the Limit Control Setting Table. It resets
automatically. The limit switch operates when a high temperature condition, caused by inadequate supply air flow
occurs, thus shutting down the ignition control and closing
the main gas valves and energizing the blower.
2. Centrifugal Switch (CS). If the draft motor should fail, the
centrifugal switch attached to the shaft of the motor
prevents the ignition controls and gas valves from being
energized.
3. Redundant Gas Valve. There are two separate gas valves
in the furnace. Each valve contains a main and a redundant
valve. The redundant valves are located upstream of the
main gas valves. Should either or both of the main gas
valves fail in the open position the redundant valves serve
as back-ups and shuts off the flow of gas.
Unitary Products Group
G V 1
G A S
V A L V E
S E N S O R # 1
G V 2
G A S
V A L V E
IG N IT O R # 2
IG N IT O R # 1
S E N S O R
# 2
B U R N E R C O M P A R T M E N T
FIG 13-GAS VALVE AND CONTROLS
190°F. It is a manual reset switch. If AUX trips, then the
primary limit has not functioned correctly. Replace the
primary limit.
HEAT ANTICIPATOR SETPOINTS
It is important that the anticipator setpoint be correct. Too high
of a setting will result in longer heat cycles and a greater
temperature swing in the conditioned space. Reducing the
value below the correct setpoint will give shorter “ON” cycles
and may result in the lowering of the temperture within the
conditioned space.
Gas Valve
Honeywell VR8440
White-Rodgers 36C68
Anticipator Setpoint
1st Stage
2nd Stage
0.30 amp
0.11 amp
17
530.18-N6Y
START-UP
PRE-START CHECK LIST
Complete the following checks before starting the unit.
inches, nor the operating pressure drop below 5.0" for
natural gas units. If gas pressure is outside these limits,
contact the local gas utility for corrective action.
1. Check the type of gas being supplied. Be sure that it is the
same as listed on the unit nameplate.
MANIFOLD GAS PRESSURE ADJUSTMENT
2. Make sure that the vent and combustion air hoods have
been properly installed.
Small adjustments to the high-fire gas flow may be made by
turning the pressure regulator adjusting screw on the automatic
gas valve.
OPERATING INSTRUCTIONS
CAUTION: This furnace is equipped with an intermittent pilot
and automatic re-ignition system. DO NOT attempt
to manually light the pilot.
TO LIGHT PILOT AND MAIN BURNERS:
1. Turn “off” electric power to unit.
2. Turn room thermostat to lowest setting.
3. Turn gas valve knob to “on” position.
4. Turn “on” electric power to unit.
5. Set room thermostat to desired temperature.
(If thermostat “set” temperature is above room temperature,
pilot burner ignition will occur and, after an interval to prove
pilot flame, main burners will ignite).
Adjust as follows:
1. Remove the cap on the regulator. It’s located next to the
push-on electrical terminals.
2. To decrease the gas pressure, turn the adjusting screw
counterclockwise.
3. To increase the gas pressure, turn the adjusting screw
clockwise.
NOTE: The correct manifold pressure for these furnaces is
3.65 IWG ±0.3.
B U R N E R A S S E M B L Y B R A C K E T
F L A M E S E N S O R B U L B
TO SHUT DOWN:
1. Turn “off” electric power to unit.
2. Depress knob of gas valve while turning to “off” position.
POST-START CHECK LIST (GAS)
1 /8 " G A P B E T W E E N C A R R Y -O V E R
T U B E A N D F L A M E S E N S O R B U L B
After the entire control circuit has been energized and the
heating section is operating, make the following checks:
1. Check for gas leaks in the unit piping as well as the supply
piping.
C A R R Y -O V E R T U B E
FIG. 15 - PROPER FLAME ADJUSTMENT
2. Check for correct manifold gas pressures. See “Checking
Gas Input”.
PILOT CHECKOUT
3. Check the supply gas pressure. It must be within the limits
shown on rating nameplate. Supply pressure should be
checked with all gas appliances in the building at full fire. At
no time should the stand by gas line pressure exceed 13
The pilot flame should envelope the end of the flame sensor.
To adjust pilot flame, (1) remove pilot adjustment cover screw,
(2) increase or decrease the clearance for air to the desired
level, (3) be sure to replace cover screw after adjustment to
prevent possible gas leakage.
ON-OFF CONTROL
HIGH FIRE ADJ.
(UNDER SCREW)
Put the system into operation and observe through complete
cycle to be sure all controls function properly.
BURNER INSTRUCTIONS
To check or change burners, pilot or orifices, CLOSE MAIN
MANUAL SHUT-OFF VALVE AND SHUT OFF ALL ELECTRIC
POWER TO THE UNIT.
1. Remove the screws holding either end of the manifold to
the burner supports.
PILOT ADJ.
(UNDER SCREW)
2. Open the union fitting in the gas supply line just upstream
of the unit gas valve and downstream from the main manual
shut-off valve.
FIG. 14 - TYPICAL GAS VALVE
18
Unitary Products Group
530.18-N6Y
3. Remove the gas piping closure panel.
4. Disconnect wiring to the gas valves and spark ignitors.
Remove the manifold-burner gas valve assembly by lifting
up and pulling back.
static pressures. Use Model 1LD0416 for 15 ton units and
Model 1LD0417 for 20 ton units. Refer to the Blower Motor and
Drive Data Table.
Note the following:
1. The supply air CFM must be within the limitations shown in
the Applications Data Table.
2. Pulleys can be adjusted in half turn increments.
3. The tension on the belt should be adjusted as shown in the
Belt Adjustment figure.
FIG. 16 - TYPICAL FLAME APPEARANCE
Burners are now accessible for service.
Reverse the above procedure to replace the assemblies. Make
sure that burners are level and seat at the rear of the heat
exchanger.
BURNER AIR SHUTTER ADJUSTMENT
Adjust burner shutters so no yellow flame is observed in the
heat exchanger tubes.
CHECKING SUPPLY AIR CFM
The RPM of the supply air blower will depend on the required CFM,
the unit accessories or options and the static resistances of both
the supply and the return air duct systems. With this information,
the RPM for the supply air blower and the motor pulley adjustment
(turns open) can be determined from the Blower Performance
Data Tables.
Start the supply air blower motor. Adjust the resistances in both
the supply and the return air duct systems to balance the air
distribution throughout the conditioned space. The job
specifications may require that this balancing be done by
someone other than the equipment installer.
To check the supply air CFM after the initial balancing has been
completed:
1. Remove the two 5/16 inch dot plugs from the blower motor and the
filter access panels shown in the Dimensions and Clearances figure.
2. Insert at least 8 inches of 1/4 inch tubing into each of these
holes for sufficient penetration into the air flow on both sides
of the indoor coil.
NOTE: The tubes must be inserted and held in a position
perpendicular to the air flow so that velocity pressure will not affect the static pressure readings.
3. Using an inclined manometer, determine the pressure drop
across a dry evaporator coil. Since the moisture on an
evaporator coil may vary greatly, measuring the pressure
drop across a wet coil under field conditions would be
High speed drive accessories (containing a smaller blower
pulley and a shorter belt) are available for applications requiring
the supply air blower to produce higher CFM’s and/or higher
FIG.17 - BELT ADJUSTMENT
Unitary Products Group
FIG. 18 - PRESSURE DROP ACROSS A DRY INDOOR
COIL VS SUPPLY AIR CFM
19
530.18-N6Y
inaccurate. To assure a dry coil, the compressors should be
deactivated while the test is being run.
4. Knowing the pressure drop across a dry coil, the actual
CFM through the unit and clean 2 inch filters, can be
determined from the curve in Pressure Drop vs. Supply Air
CFM figure.
WARNING: Failure to properly adjust the total system air quantity can result in extensive blower damage.
After readings have been obtained, remove the tubes and
reinstall the two 5/16 inch dot plugs that were removed in Step
1.
NOTE:
DE-ENERGIZE THE COMPRESSORS BEFORE TAKING ANY TEST
MEASUREMENTS TO ASSURE A DRY INDOOR COIL.
1. Turn off all other gas appliances connected to the gas meter.
2. With the furnace turned on, measure the time needed for
one revolution of the hand on the smallest dial on the meter.
A typical gas meter usually has a 1/2 or a 1 cubic foot test
dial.
3. Using the number of seconds for each revolution and the size
of the test dial increment, find the cubic feet of gas consumed
per hour from the Gas Rate - Cubic Feet Per Hour Table.
If the actual input is not within 5% of the furnace rating (with
allowance being made for the permissible range of the
regulator setting), replace the orifice spuds with spuds of the
proper size.
ADJUSTMENT OF TEMPERATURE RISE
NOTE To find the Btu input, multiply the number of cubic feet of
gas consumed per hour by the Btu content of the gas in
The temperature rise (or temperature difference between the return
air and the heated air from the furnace) must lie within the range shown
on the ETL rating plate and the data in the Gas Heat Application Table.
TABLE 14 - GAS RATE - CUBIC FEET PER HOUR
CFM =
Btuh Input x 0.8
1.08 x oF Temp. Rise
After the temperature rise has been determined, the cfm can
be calculated as follows:
After about 20 minutes of operation, determine the furnace
temperature rise. Take readings of both the return air and the
heated air in the ducts (about six feet from the furnace) where
they will not be affected by radiant heat. Increase the blower
cfm to decrease the temperature rise; decrease the blower cfm
to increase the rise. Refer to the Blower Motor and Drive Data
Table.
BELT DRIVE BLOWER
All units have belt drive single-speed blower motors. The
variable pitch pulley on the blower motor can be adjusted to
obtain the desired supply air CFM.
Seconds
for One
Rev.
4
6
8
10
12
14
16
18
20
22
24
26
28
Size of Test Dial
1/2 cu. ft.
1 cu. ft.
450
300
228
180
150
129
113
100
90
82
75
69
64
900
600
450
360
300
257
225
200
180
164
150
138
129
Example: By actual measurement, it takes 13 seconds for the hand on the 1-cubic
foot dial to make a revolution with just a 300,000 Btuh furnace running. Read
across to the column in the table above, headed “1 Cubic Foot”, where you will see
that 278 cubic feet of gas per hour are consumed by the furnace at that rate.
Multiply 278 x 1050 (the Btu rating of the gas obtained from the local gas company).
The result is 292,425 Btuh, which is close to the 300,000 Btuh rating of the furnace.
CHECKING GAS INPUT
NATURAL GAS
SECURE OWNER’S APPROVAL: When the system is functioning properly, secure the owner’s approval. Show him the location
of all disconnect switches and the thermostat. Teach him how to start and stop the unit and how to adjust temperature settings
within the limitations of the system.
20
Unitary Products Group
530.18-N6Y
MAINTENANCE
your particular locality (contact your gas company for
this information - it varies widely from city to city.)
NORMAL MAINTENANCE
CAUTION: Prior to any of the following maintenance procedures, shut off all electric power to the unit to
prevent personal injury.
Periodic maintenance normally consists of changing or
cleaning filters and (under some conditions) cleaning the main
burners.
FILTERS - Inspect once a month. Replace disposable or clean
permanent type as necessary. DO NOT replace permanent
type with disposable. The dimensional size of the replacement
filter must be the same as the replaced filter.
MOTORS
Outdoor fan motors are permanently lubricated and require no
maintenance.
Ventor motor is factory lubricated for an estimated 10 year life.
Indoor Blower Motor and Drive - The indoor blower motor
features ball bearings that do not require periodic lubrication.
Periodic lubrication of the motor and bearings can extend the
life of components but is optional.
CAUTION: D a ma ge c an o c c ur if th e bear ings ar e
overlubricated. Use grease sparingly.
WARNING: Perform all maintenance operations on the blower
motor with electric power disconnected from the
unit. Do not attempt to lubricate bearings with the
unit in operation.
On an annual basis, check the motor for accumulations of dust,
etc. that may block the cooling slots in the motor shell. Check
for loose, damaged or misaligned drive components. Check
that all mounting bolts are tight. Replace defective parts as
required.
If desired, every three years remove both pipe plugs at each
end shell and clean out any hardened grease or foreign matter.
Replace one plug on each end with a clean grease fitting. Using
a low pressure grease gun, pump grease (Chevron SRI-2 or
equivalent) into the bearing cavity until new grease shows at
the open port. Do not over lubricate. Run the motor for ten
minutes until excess grease is purged from the cavity. Replace
the plugs.
On 20 ton only, units are supplied with blower shaft bearings
that do not require maintenance but may be relubricated if
desired. Every three years, using a low pressure grease gun,
pump grease into the bearing grease fitting until grease just
begins to show at the seals. Do not over lubricate. Use any
lithium base grease recommended for ball bearing service.
OUTDOOR COIL - Dirt should not be allowed to accumulate
on the outdoor coil surface or other parts in the air circuit.
Cleaning should be as often as necessary to keep coil clean.
Use a brush, vacuum cleaner attachment, or other suitable
means. If water is used to clean coil, be sure electric power to
the unit is shut off prior to cleaning.
explained under “BURNER AIR SHUTTER ADJUSTMENT”. If
it is not possible to adjust for the proper flame, the burners may
need cleaning.
TO CLEAN BURNERS - Remove them from the furnace as
explained in “Burner Instructions”. Clean burners with hot water
applied along top of the burner.
COMBUSTION AIR DISCHARGE - Visually inspect discharge
outlet periodically to make sure that the buildup of soot and dirt
is not excessive. If necessary, clean to maintain adequate
combustion air discharge.
CLEANING FLUE PASSAGES AND HEATING
ELEMENTS
With proper combustion adjustment the heating element of a
gas fired furnace will seldom need cleaning. If the element
should become sooted, it can be cleaned as follows:
1. Remove the burner assembly as outlined in “BURNER
INSTRUCTIONS”.
2. Remove the roof over the gas heat section.
3. At the top plate from the top draft blower housing and the
top draft blower wheel.
4. Remove the screws holding the top of the flue collector box.
Carefully remove the top of the flue collector box without
ripping the adjacent insulation. Then remove the center
divider plate separating the upper and lower flue boxes.
5. On the inside of the flue collector box, remove the flue
baffles from the tube interiors. Note the last bend of the
baffle fits tightly against the tube forcing the end of the baffle
to lock into the tube collar. This collar is formed when the
tube is expanded into the end sheet. To remove, move the
end of the baffle toward the center of the tube releasing the
end of the baffle from the tube collar, then pull straight out
of the tube. Refer to Typical Flue Baffle figure.
6. Using a wire brush on a flexible wand, brush out the inside
of each heat exchanger from the burner inlet and flue outlet
ends.
7. Brush out the inside of the flue collector box and the flue
baffles.
8. Run the wire brush down the vent hoods from the flue
collector end.
9. If soot build-up is particularly bad, remove the vent motor
and clean the wheel and housings. Run the wire brush down
the flue extentions at the outlet of the vent housings.
10. After brushing is complete, blow all brushed areas with air
or nitrogen. Vacuum as needed.
11. Replace parts in the order they were removed in Steps
1 thru 4.
12. When replacing the center and top of the flue collector box,
be careful not to tear the adjoining insulation.
NOTE: Exercise care when cleaning the coil so that the coil
fins are not damaged.
Do not permit the hot condenser air discharge to be
obstructed by overhanging structures of shrubs.
BURNER & PILOT - Periodically (at least annually at the
beginning of each heating season) make a visual check of the
pilot and main burner flame. If necessary, adjust main burner
primary air shutters to give a distinct, sharp blue flame as
Unitary Products Group
FIG. 19 - TYPICAL FLUE BAFFLE INSTALLATION
21
530.18-N6Y
TROUBLESHOOTING
13. Ensure that all seams on the vent side of the combustion
system are air tight. Apply a high temperature (+500°F)
sealing compound where needed.
WARNING: Troubleshooting of components necessarily requires opening the electrical control box with the
power connected to the unit. Use extreme care
when working with live circuits! Check the unit
nameplate for the correct line voltage and set the
volt meter to the correct range before making any
connections with line terminals.
WARNING: Prior to any of the following maintenance procedures, shut off all electric power to the unit to
prevent personal injury.
CAUTION: Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and
dangerous operation. Verify proper operation after
servicing.
NOTE To find the Btu input, multiply the number of cubic feet of
gas consumed per hour by the Btu content of the gas in
your particular locality (contact your gas company for this
information - it varies widely from city to city.)
1. The indoor blower motor is a non-inherently protected
three-phase motor. Protection is provided by an overload
relay for overcurrent and fuses for short circuit. If the motor
fails to run, check the line voltage circuit and control voltage
circuit per the following procedure:
a. If the Indoor Blower Motor does not operate, check
visually that contactor M3 is pulled in. If so, check for
line voltage between all three phases at the line terminals of the Blower Overload Relay (BOR). If line voltage
is found, check the leads to the blower motor for open
circuit. If line voltage is found at the motor leads (inside
the conduit box on the motor shell), disconnect the
motor and check for open windings per the motor wiring
diagram. If open windings are found, replace the motor.
If line voltage is not found at the BOR, trace the leads
back to the field supply terminal block, checking for an
open circuit or blown fuses.
b. If the contactor M3 is not pulled in, check for control
voltage (24V) at the M3 coil. If voltage is found, replace
the contactor. If control voltage is not found at M3, check
for voltage across terminals 95 & 96 of the BOR. If
voltage exists, the BOR is open on overload. The BOR
should be set to the auto reset position. The BOR must
cool down in order to reset. If the BOR will not reset,
replace the BOR. If the BOR resets and M3 pulls in, but
the indoor blower motor will still not run, refer to para.
(a) for troubleshooting the line voltage supply circuit. If
control voltage is not found at the BOR, trace the circuit
back to the relay board and thermostat per the unit
wiring diagram. Replace any defective components.
2. Draft motor operates and furnace lights but supply air
blower does not start after a short time delay with room
thermostat fan switch set to “AUTO”.
a. Set fan switch to “ON”. If blower motor runs, go to Step f.
If it does not, check to see if line voltage is being
supplied to the contacts of the contactor (M3), and if the
contactor is pulled in. Check for loose wiring.
b. If contactor (M3) is pulled in, proceed with the troubleshooting steps indicated in Step 1 above.
c. If (M3) is pulled in and the blower motor still does not
run, replace the blower motor.
d. If (M3) is not pulled in, check for 24 volts at the (M3) coil.
If 24 volts is present, replace the (M3) contactor.
e. If 24 volts is not present at the (M3) coil, check for loose
24 volt wiring back to the relay board. Check control
wiring to the room thermostat. If all is fine, replace the
relay board.
f. If the blower motor runs with the fan switch in the “ON”
position but does not run soon after the furnace has
ignited with the fan switch in the “AUTO” position, check
for loose 24 volt wiring between the relay board in the
main control box, the Mate-N-Lok connector in the
partition between the evaporator and gas heat sections
and the time delay relay (ETD).
g. If all control wiring is fine, check for 24 volts at the relay
board. If 24 volts is present, replace the relay board. If
24 volts is not present, replace the (ETD) relay.
NOTE: The furnace may shut itself down on a high temperature condition during the procedure, but this will not
effect the test if it is done within 5 minutes of furnace
shut-down.
3. The supply air blower operates but the draft motor does not
when the room thermostat is set to call for heat and the fan
switch in the “ON” position.
a. The draft motor has inherent protection. If the motor shell
is hot to the touch, wait for the internal overload to reset.
b. If the motor shell is cold with the room thermostat calling
for heat, check for line voltage at the motor’s Mate-NLok connector attached to the evaporator partition. If
line voltage is present, replace the draft motor.
c. If line voltage is not present, check for line voltage at the
heat relay (RW1) contacts in the main control box and
check to see if the (RW1) is pulled in.
d. If the (RW1) relay is pulled in, check for a loose line
voltage connection.
e. If the (RW1) relay is not pulled in, check for 24 volts at
the (RW1) coil. If 24 volts is present, replace the (RW1)
relay. If 24 volts is not present, check for a loose 24 volt
connection back to the relay board and check the connections from the room thermostat to the relay board. If
all connections are correct, replace the relay board.
4. The draft motor runs but the furnace does not light and the
sparker does not spark.
a. The ignition control (IC1, IC2) may be locked out due to
either a flame roll out or 100% shut off. These safety
features are described above. If lock-out has occurred,
24V must be removed from the ignition controls. This is
done at the unit or by resetting the room thermostat.
After resetting 24V, check for proper furnace operation.
Cont’d.
22
Unitary Products Group
530.18-N6Y
TROUBLESHOOTING - Cont’d.
If lock-out continues to occur, locate the source of the
problem and correct.
b. Check all 24 volt connections from the relay board to
and in the gas heat section. Check low voltage connections to the (ETD) located in the control box.
c. If the furnace is hot, it may be out on an over-temperature condition, wait for limit reset.
d. If the furnace is cold, check for 24 volts at wire 241
attached to the electrical time delay (ETD) located in the
main control box. If 24 volts is not found, replace the
ETD.
e. 24 volts is found at wire 241, remove the wires attached
to the (TDR) and with a VOM, check for continuity
across contacts 1 and 2. If none is found, the (TDR) is
open and must be replaced. If there is continuity, re-attach the wires.With the draft motor running, check for
24 volts at terminal 4 of (RW1-2) and (RW2-1). If 24 volts
is not present, the centrifugal switch (CS) has not closed
or has gone bad. Check the line voltage to the unit - if
it is correct, replace the draft motor. If line voltage is low,
call the power company.
f. Check for 24V at terminal 2 of (RW1-2 and RW2-1). If
24V is not present, check for 24V at (RW1 and RW2)
relay coils. If these relays are pulled in, then check for
a loose connection at terminal 2 and terminal 4 of each
relay. If no problem is found, then replace (RW1 and/or
RW2) as required.
g. If 24 volts is present at the ignitor controls, check all
control wiring at the ignitor controls and the high tension
wire to the ignitors. Check that the ground wires from
the ignitor controls, the gas valves and pilot burners are
all intact and making good electrical connection. Check
to make sure that the ceramic insulator on the pilot
ignitors or sensors is not broken or cracked, if all are
intact, replace the ignition control IC1 or IC2.
5. The draft motor runs and the sparker sparks at the pilot
burner but the pilot does not ignite and a gas odor is not
detected at the draft motor outlet.
a. Check to make sure gas is being supplied to the unit.
Make sure that the gas pressure to the unit is within the
proper limits as described in the “POST START CHECK
LIST” and that the pilot adjust screw is allowing some
flow of gas as described in “PILOT CHECKOUT”.
b. Check all wiring between the ignitor control and the gas
valve. Check to make sure the ground connections are
intact.
c. If the wiring is intact, check for 24 volts across terminals
“PV” and “COMMON” on the ignitor control. If 24 volts
is not present, replace the ignitor control.
Unitary Products Group
d. If 24 volts is present, remove the pilot burner and
remove the pilot orifice from the pilot burner. The orifice
is removed in the direction opposite the flow of gas.
Inspect the orifice for obstruction. If it is clear, replace
the main gas valve.
6. The sparker sparks at the pilot burner but the pilot does not
ignite and a gas odor is detected at the draft motor outlet.
a. Adjust the pilot adjust screw on the gas valve as described in “PILOT CHECKOUT”.
b. Check the supply pressure as described in “POST
START CHECK LIST”. Make adjustments as necessary.
c. Check the pilot orifice for obstruction as described in
para. 5d. Clean as needed but the problem should not
be the gas valve.
7. The pilot burner ignites but the sparker continues to spark
and the main burners do not ignite.
a. Make the same checks and adjustment as described in
para. 6.
b. Make sure that the pilot burner is not bent or damaged.
c. Make sure that the ground connections at the pilot
burner, gas valve and ignitor control are intact. Check
the high tension wire for good electrical connection. If
all are intact, replace the ignitor module.
8. The pilot burner lights and the spark stops but the main
burners do not light.
a. Check electrical connections between the ignitor control and the gas valve. If intact, check for 24 volts across
terminals “MV” and “COMMON” terminals. If no voltage
detected, replace ignitor control. If voltage is present,
replace gas valve.
9. Furnace lights with roll-out or one burner has delayed
ignition.
a. Make sure that the pilot burner is aligned properly with
the carryover as described in “PILOT CHECKOUT”.
b. Make sure that the carryovers on adjoining burners are
screwed fast and are level with respect to one another.
10. Main burners light but exhibit erratic flame characteristics.
a. Adjust air shutters as described in “BURNER AIR
SHUTTER ADJUSTMENT”.
b. Check the main burner orifices for obstruction and
alignment. Removal procedure is described in
“BURNER INSTRUCTIONS”. Clean or replace burner
orifices and burners as needed.
23
REPLACEMENT PARTS
COMPRESSOR SECTION
GAS HEAT SECTION
FABRICATED PARTS SECTION
• Hermetic compressor
• Compressor mounting
• Blower motor
• Fan motor
• Ventor motor
•
•
•
•
•
•
•
•
•
•
•
•
ELECTRICAL SECTION
AIR MOVING SECTION
MOTOR SECTION
•
•
•
•
•
•
•
•
•
Ignition control
Relay board
Contactor
Circuit breaker
Temperature controls
Capacitors
Relays
Transformers
Connectors
Heat exchanger
Gas valve
Pilot
Flame sensor
Spark ignitor
Gas manifold
Gas burner
Panels
Posts
Covers Drain pans
Base rails
Air hoods
MISCELLANEOUS SECTION
• Blower wheel
• Blower wheel housing
• Air inlet hood screen
• Fan guard
• Air filters
REFRIGERANT SECTION
•
•
•
•
•
Evaporator coil
Evaporator coil header
Expansion valve assembly
Condenser coil
Condenser coil header
TO OBTAIN PARTS INFORMATION: Replacement parts and information from OUR current parts list for this unit are available to
your servicing contractor through our local distributor. The name and address of our nearest distributor may be obtained by
consulting the Yellow Pages of a local telephone directory.
IMPORTANT: In order to supply the correct part or information from the parts list, our distributor will need to be provided with the
complete model number listed on the rating plate located on your unit. See page 2 for Product Nomenclature.
WARNING: IMPROPER INSTALLATION, ADJUSTMENT, SERVICE OR MAINTENANCE CAN CAUSE INJURY OR PROPERTY
DAMAGE. CONSULT A QUALIFIED INSTALLER, SERVICE AGENCY OR YOUR LOCAL GAS SUPPLIER FOR INFORMATION
OR ASSISTANCE.
Unitary Products Group
5005 York Drive, Norman, Oklahoma 73069
Subject to change without notice. Printed in U.S.A
Copyright  by York International Corporation 2000. All Rights Reserved.
Supersedes: 530.18-N6Y (1298)
Code: SBY
530.18-N6Y(500)